TY  - JOUR
AU  - Shephard, G. C.
TI  - An Elementary Proof of Gram's Theorem for Convex Polytopes
JO  - Canadian journal of mathematics
PY  - 1967
SP  - 1214
EP  - 1217
VL  - 19
IS  - 1
UR  - http://geodesic.mathdoc.fr/articles/10.4153/CJM-1967-110-7/
DO  - 10.4153/CJM-1967-110-7
ID  - 10_4153_CJM_1967_110_7
ER  -